Novel device and method for peproducing printed matter



Oct. 10, 1967 J. E. HAMMONDS 3,346,431

NOVEL DEVICE AND METHOD FOR REPRODUCING PRINTED MATTER Filed Feb. 25, 1964 I N VEN TOR. JOHN E. f/Af/f/0N05 Arne/v5 vs United States Patent 3,346,431 NOVEL DEVICE AND METHOD FDR REPRODUCING PRINTED MATTER John E. Hammonds, 5254 E. 20th St., Tucson, Ariz. 85711 Fiied Feb. 25, 1964, Ser. No. 347,261 11 Claims. (Cl. 156-235) This invention relates to a novel reproducing device and method. More particularly, the invention concerns a novel device and method for copying a page of printed material such as the printed text of a book, drawings, tables of data and the like.

A prime feature of the invention is the provision of devices and methods for copying such printed material without the use of expensive and complicated duplicating machines.

In the past several years considerable attention has been directed to the development and commercialization of machines and systems for duplicating and copying printed material. These developments have reached a rather high degree of sophistication and there are now commercially available machines and equipment which perform this task extremely Well. These machines and apparatus are based on several different modes of operation, for example, the electrodeposition of carbon particles in the interstices of reproducing paper (xerography) and the use of papers which are specially treated to render them heat-sensitive or light-sensitive. However, each of the presently available copying systems requires the employment of complicated, expensive and bulky apparatus, thus severely limiting the utility of these systems especially where the material to be copied is located at points remote from the necessarily semi-permanent loca tion of the copying equipment. Therefore, it would be highly advantageous to have available a relatively simple and inexpensive system for copying printed material at remote locations and to have such a system available to persons and organizations whose needs for making such copies are only occasional and who, therefore, cannot economically justify the purchase and maintenance of complicated and expensive copying equipment.

Accordingly, it is a prime object of my invention to provide devices and methods for copying or reproducing printed indicia which do not require the employment of complicated and expensive equipment and apparatus.

Another object of my invention is to provide such devices and methods which are relatively inexpensive.

Still a further object of my invention is to provide such devices and methods which will reproduce in rather fine detail the printed indicia to be copied.

Another object of my invention is to provide a completely portable device which is capable of reproducing printed indicia.

Gther objects and advantages of my invention will become apparent from the following description taken in connection with the drawings in which:

FIGURE 1 is a perspective view of a portion of the reproducing laminate of my invention showing the general construction of the laminate;

FIGURE 2 is a perspective view of the complete reproducing device of the invention showing the backing sheet slightly separated from the reproducing sheet for purposes of clarity;

FIGURE 3 is a perspective view of the device of FIG- URE 2 arranged in the copying or reproducing position; and

FIGURE 4 is a sectional perspective view of the device of the invention after the copy has been made, illustrating in greater detail the mode of operation of the device.

Briefly, in accordance with my invention, I provide a device for use in reproducing printed indicia comprising a laminate of a transparent support sheet and a thin film of a normally substantially transparent rubbery organic polymer which is swollen when contacted with a hydrocarbon solvent. Advisably the polymer should have a relatively low degree of cross-linking or vulcanization. This device is used in the method of my invention as follows:

The printed material to be copied will typically be carried upon a semi-porous substrate such as paper, cloth and the like. The substrate is treated with a hydrocarbon solvent which normally swells natural and synthetic rubbers, the solvent being applied to the substrate in at least an amount suflicient to saturate the surface areas of the substrate which do not contain printed indicia but in less than an amount which would damage the substrate and the printed indicia. The substrate can be treated with the hydrocarbon solvent by various methods such as spraying the solvent onto the paper or by applying it from a sponge wiped lightly across the surface of the substrate. The solvent soaks into the substrate saturating the surface areas of the substrate which do not contain printed indicia but, the printing ink masks the substrate and prevents the hydrocarbon solvent from saturating the substrate beneath the printed indicia. The small amounts of solvent which may diffuse into the substrate beneath the ink apparently do not have a deleterious effect. Of course, care should be exercised not to apply excessive quantities of the solvent to the substrate as this will not only reduce the quality of the reproduction but may also damage the substrate and the printed indicia. In general, it is desired to employ in this step as small an amount of solvent as possible and this amount can be readily determined by making one or two trials. Thus, it is usually only necessary to spray or apply to the surface of the substrate an amount of solvent which will just dampen the surface thereof without forming pools or drops of the solvent on the surface of the substrate. However, if excess solvent i inadvertently applied, the excess can be taken up with a blotter or can simply be allowed to evaporate before proceeding.

After the substrate has been treated as aforesaid with the hydrocarbon solvent the reproducing laminate hereabove described is pressed into wetting contact with the solvent-dampened substrate with the side of the laminate bearing the thin film of rubbery polymer contacting the substrate. The solvent absorbed in the surface of the substrate contacts the rubbery polymer thereby changing the nature of the polymer, so that when the laminate is lifted from contact with the substrate the polymer is rendered opaque in the areas of the laminate corresponding to the areas of the substrate where no printing appears. Obviously, the laminate must remain in contact with the substrate for a length of time suflicient to allow the solvent in the substrate to contact the appropriate areas of the reproducing laminate. Thereafter, the reproducing sheet is separated from the substrate and the laminate then appears as a negative reproduction of the printed substrate, i.e., the portions of the laminate corresponding to the printed area of the substrate are substantially clear while the portions of the laminate corresponding to the unprinted areas of the substrate are substantially opaque. The thus developed reproducing laminate can be used to good advantage in this condition. For example, the debackground and it can be used as a slide for use in a projector. However, most conveniently, the developed reproducing laminate is advantageously backed with a sheet of opaque dark-colored material to render greater contrast between the .developed and the nu-developed areas.

Turning now to the drawings, FIGURE 1 is a greatly magnified perspective view of a portion of the reproducing laminate of the invention comprising a transparent support sheet 1 and a thin film 2 of a normally substantially transparent rubbery organic polymer of the type herein described. The support sheet can be madeof any of the commonly known transparent sheeting materials 'such as, for example, cellulosic materials such as cellophane, cellulose acetate, cellulose butyrate and the like, synthetic thermoplastics such as polymers of ethylenically unsaturated polymerizable organic monomers, for ex ample, the polymerized halogenated vinyl compounds such as polyvinylchloride and polyvinylfluoride and the polyolefins such as polyethylene, polypropylene, copolymers of ethylene with various unsaturated comonomers,

' for example, ethylene-alkyl acrylate copolymers such as ethylene-methyl acrylate and ethylene-methyl methacrylate copolymers, and copolymers of ethylene with various vinyl esters, for example, ethylene-vinyl acetate copolymers. Thus, the precise nature of the material used in the support sheet is not highly critical and, in general, it is desirable 'to employ materials capable of fabrication into flexible transparent sheets, advantageously of a thickness of from about 1 to about mils and which, in such thicknesses, have suitable mechanical strength properties. In the preferred practice of the invention, I employ transparent polyvinylfluoride, cellulosic materials or the recently developed high-clarity polymers of ethylene, particularly the ethylene-vinyl acetate copolymers of low crystallinity and unusually high clarity.

The rubbery organic polymer employed as the thin film of the reproducing laminate can be any of the normally substantially transparent rubbery organic polymers, advisably having a low degree of crosslinking or vulcanization, which are swollen when contacted with a hydrocaribon solvent. For example, I have successfully employed such materials as neoprene, GRS rubbers, GRN rubbers, SKB rubbers, SKS rubbers, the SKN rubbers, the butyl rubbers, the poly-isobutylene rubbers as well as certain natural rubbers. The preferred form of the rubber for use in preparing the laminate is that of a dis-' persion of milledirubber in an appropriate solvent such as hexane. At present the preferred rubbers used in the practice of my invention are the neoprene (poly-chloroprene) andthe GRS and GRN-type rubbers. Of course, the aforesaid rubbers can also contain appropriate quantities of common rubber additives such as for example pigments and anti-oxidants (such as 2,6-ditertiarybutyl-4- sheet, the thickness of the film of rubbery polymer which.

is employed in preparing the reproducing laminate is not highly critical, in general a thickness of from about 0.05 r

of the other laminae or that an adhesive bonding material be disposed between the laminae which wets the surface of both the support sheet and the film of rubbery polymer. As an example, an adhesive commercially obtainable under the tradename Acorn SY 210()1 can be advantageously. employed to provide for optical contact between a cellophane support sheet and a neoprene rubber film.

FIGURE 2 is a perspective view of a preferred embodiment of the invention wherein a substantially rectangular sheet 3 of the reproducing laminate of FIGURE 1 is combined in a unitary assembly with an opaque darkcolored backing sheet 4, for example .a black paper, having dimensions substantially equal to the dimensions of the reproducinglaminate, the backing sheet being flexibly attached, for example by a suitable adhesive, to

the reproducing laminate along one common edge thereof,

ing laminate has been developed the opaque backing sheet can be pressed into firm contact with the reproducing laminate to provide a unitary sheet assembly.

FIGURE 3 is a perspective view of the device of FIG- URE 2 arranged in position upon a piece of printed material 5 with the transparent reproducing laminate 6 being 7 positioned upon the printed material with the rubbery film-side down and the opaque backing sheet 7 being disposed away from the printed material but still attached 7 to the reproducing laminate along the common top edges thereof. Of course, as described hereabove, the material to be copied has been treated with the hydrocarbon solvent prior to disposing the device upon the printed material as shown in FIGURE 3. The reproducing laminate 6 is smoothed and pressed into firm contact with the printed material and allowed to remain in such contact for a length of time sufl'icient to allow the solvent in the blank spaces of the printed material to contact the thin film of rubbery polymer disposed on the underside of the reproducing laminate. This will not require an inordinate length of time; for example, I have found that contact times of less than 15 seconds, even as low as 0.5 second,

are sufiicient. Thereafter, the developed reproducing laminate is separated from the printed material suitably by grasping the common edges'of the attached laminate and backing sheet and lifting and carefully peeling the laminate from the surface of the printed material. The lifting of the laminate from the substrate causes 'the solvent-contacted portions of the rubbery film to become opaque. Thereafter the developed laminate may be smoothed onto the backing sheet.

FIGURE 4 is a greatly magnified perspective view of a section of the developed laminate showing how the image is produced. .The opaque dark-colored backing sheet 9 shows through the substantially transparent portions 10 of the thin film of rubbery polymer 11 when viewed through the transparent support sheet 12 from a direction indicated by the arrow 13. Although not shown as such in the drawings the opacity of the opaque areas of the rubbery film is caused by the presence of a profusion of microgels in the opaque areas.

Advantageously, the top surface of the transparent support sheet can'be provided with a matte finish' to reduce the glare caused by reflected light.

The afore-described methods and devices exhibit extremely fine sensitivity when employed to copy highquality printing, e.g., where inks containing varnish or.

'drying oil vehicles have been employed, and are also useful in copying a wide variety of other types of printed indicia, e.g., those produced by so-called jelled inks such as are employed in ball-point pens, India ink, and the like, although the sensitivity of the copies of such printing is somewhat reduced.

The afore-described reproducing laminates can be used according to another novel technique to lift a printed image from the surface of a printed substrate which has been previously treated as afore-described with a suitable hydrocarbon solvent. This technique can be employed when the printing ink used to prepare the original copy is an ink of the so-called balanced type, i.e., an ink which consists of a volatile solvent component contained in two liquid phases, one having low viscosity containing nearly all the pigment and binder and the other having high viscosity. For example, this balanced type of ink is currently employed in the printing of Time magazine.

The developed laminates as above-described can be used as off-set masters for producing negative copies, the opaque areas of the laminate selectively holding a suitable ink which can thereafter be transferred to the surface of a sheet of copying paper by the common off-set printing technique.

The following examples further illustrate the practice of my invention and the preferred embodiments thereof.

Example 1 This example illustrates the preparation of the reproducing laminate.

A film of neoprene latex rubber, Naugatuck brand Lotol 3307 (registered trademark U.S. Rubber Company) was cast upon a piece of glass and allowed to dry, forming a transparent film of a thickness of one mil. This rubber film was adhesively laminated to a sheet of transparent cellophane of a thickness of 2-3 mils. The adhesive was Acorn SY 2100-1 and the adhesive bond was of a thickness of 0.01 mil.

Example 2 A milled dispersion of a butadiene-styrcne copolymer (Ameripol 1300registered trademark Goodrich- Gulf) was prepared by milling the copolymer for one hour in a rubber mill and dispersing the milled rubber in hexane. This milled rubber dispersion was applied in a thickness of 0.05 mil to a 2 mil polyvinyl fluoride substrate by roller coating techniques. This reproducing laminate was used in the fabrication of the device of FIGURE 2 of the drawings as described in Example 3.

Example 3 The reproducing laminate of Example 2 was cut into a sheet of dimensions 8 /2 by 11 inches and was fabricated into the device shown in Figure 2 of the drawings by adhesively attaching a sheet of black kraft paper of similar size along the common top edges of the sheets.

A page of high quality printed matter (drying-oil based ink) was sprayed lightly with a fine mist of a petroleum fraction known commercially as white spiri to produce a slightly dampened condition with no pools or drops of white spirit visible on the surface of the printed page. The reproducing laminate was smoothed by hand into firm contact with the dampened printed page and allowed to remain in such contact for approximately three-five seconds. Thereupon, the developed laminate was lifted from the printed page and the black kraft paper backing sheet was smoothed into contact with the developed laminate. The quality of the reproduction was quite faithful in every detail.

Example 4 Several devices prepared as in the foregoing examples were used to prepare copies of typewritten and handwritten copy (ball-point pen). Although the reproductions obtained were not quite of such high quality as the reproduction of Example 2, the material was reproduced in entirely adequate detail to enable the easy reading thereof.

The hydrocarbon solvents useful in the practice of the herein-described invention are chosen according to several properties. Thus the solvent must be capable of rapid and substantially complete evaporation (it must not leave an oily film on the printed material after copying). The solvent must not destroy or unduly weaken the fibers of the substrate bearing the printed material. The solvent should not appreciably interact with the pigment or the vehicle of the ink used in preparing the printed material. Also, the solvent should have a relatively low toxicity.

Considering all of these factors the petroleum fraction described above (white spiritboiling range ISO-200 C.) is presently preferred in practing the invention although a number of other liquids will produce satisfactory images but may lack all of the advantages of white spirit. These liquids are carbontetrachloride, xylene, benzene, toluene, trichloroethylene, perchloroethylene, chloroform, ethylether, methylene chloride, and various petroleum distillate fractions.

Having described my invention and the preferred emembodiments thereof, I claim:

1. A device for use in reproducing printed indicia characterized as being a laminate consisting essentially of a flexible transparent support sheet and in optical contact therewith and aflixed thereto a thin film of a normally substantially transparent rubbery organic polymer which is swollen when treated with a hydrocarbon solvent and which has a relatively low degree of cross-linking.

2. The device of claim 1 wherein the support sheet is a transparent polyvinyl fluoride.

3. The device of claim 1 wherein the support sheet is a polymer of an ethylenically unsaturated polymerizable organic monomer.

4. The device of claim 1 wherein said rubbery organic polymer is a neoprene rubber.

5. The device of claim 1 wherein said rubbery organic polymer is a GRS rubber.

6. The device of claim 1 wherein said rubbery organic polymer is an isoprene rubber.

7. A device for use in reproducing printed indicia characterized as being a laminate consisting essentially of a flexible transparent cellulosic support sheet having a thickness of from about 1 to about 10 mils and adhesively bonded thereto in optical contact therewith a thin film of a normally substantially transparent GRS rubber of a thickness of from about .05 to about 1.5 mils.

8. A device for use in reproducing printed indicia comprising:

(a) a reproducing laminate comprising a rectangular flexible transparent support sheet and in optical contact therewith a thin film of a normally substantially transparent rubbery organic polymer which is swollen when treated with a hydrocarbon solvent;

(b) an opaque dark-colored backing sheet having dimensions substantially equal to the dimensions of the reproducing laminate; said backing sheet being adapted for separation from said reproducing laminate prior to its contact with said printed indicia and for adherence to said laminate subsequent to said contact;

said backing sheet member being flexibly attached to said reproducing laminate along one common edge thereof.

9. Method of reproducing printed indicia carried by a semi-porous substrate such as paper and the like comprising:

(a) treating the substrate with a hydrocarbon solvent which normally swells rubbers, said solvent being applied to the substrate in at least an amount sufficient to saturate the surface areas of said substrate which do not contain printed indicia but in less than an amount which damage the substrate and printed indicia;

(b) pressing into wetting contact with said substrate a reproducing laminate comprising a flexible transparent support sheet bearing thereupon in optical contact therewith a thin film of a normally substantially transparent rubbery organic polymer which is swelled when treated with the hydrocarbon solvent of step (a), the said thin film being disposed upon the surface of the reproducing laminate which contacts the substrate;

(0) maintaining the contact between the reproducing r 7 7 8 laminate and the solvent-treated substrate for a 11, Method of claim 9 wherein said rubbery polymer length of time sufficient to allow the solvent in the is amilled rubber. substrate to contact the rubbery polymer in the areas 7 corresponding to the areas of the substrate where no 7 References Cited printinglappears; 5 UNITED STATES PATENTS (d) separating the reproducing sheet from contact with the substrate thereby rendering the solvent-treated 2482094 9/1949 Chavannes et 156247 X 2 669 535 2/1954 Orr 161254 X areas opaque; and e l V p V 1 2,723,962 11/1955 Hedges et a1. 161--254 X (e) applying a sheet of opaque dark colored materra 2,759,866 8/1956 Seymour 1V61 254 XV to'the side of the reproducing laminate which bears 10 the thin film of rubbery polymer. 10. Method of claim 9 wherein said transparent 'sup- EARL BERGERT P'lmary Exammer' port sheet is polyvinyl fluoride. M. L. KATZ, Assistant Examiner. 

9. METHOD OF REPRODUCING PRINTED INDICIA CARRIED BY A SEMI-POROUS SUBSTRATE SUCH AS PAPER AND THE LIKE COMPRISING: (A) TREATING THE SUBSTRATE WITH A HYDROCARBON SOLVENT WHICH NORMALLY SWELLS RUBBERS, SAID SOLVENT BEING APPLIED TO THE SUBSTRATE IN AT LEAST AN AMOUNT SUFFICIENT TO SATURATE THE SURFACE AREAS OF SAID SUBSTRATE WHICH DO NOT CONTAIN PRINTED INDICIA BUT IN LESS THAN AN AMOUNT WHICH DAMAGE THE SUBSTRATE AND PRINTED INDICIA; (B) PRESSING INTO WETTING CONTACT WITH SAID SUBSTRATE A REPRODUCING LAMINATE COMPRISING A FLEXIBLE TRANSPARENT SUPPORT SHEET BEARING THEREUPON IN OPTICAL CONTACT THEREWITH A THIN FILM OF A NORMALLY SUBSTANTIALLY TRANSPARENT RUBBERY ORGANIC POLYMER WHICH IS SWELLED WHEN TREATED WITH THE HYDROCARBON SOLVENT OF STEP (A), THE SAID THINFILM BEING DISPOSED UPON THE SURFACE OF THE REPRODUCING LAMINATE WHICH CONTACTS THE SUBSTRATE; (C) MAINTAINING THE CONTACT BETWEEN THE REPRODUCING LAMINATE AND THE SOLVENT-TREATED SUBSTRATE FOR A LENGTH OF TIME SUFFICIENT TO ALLOW THE SOLVENT IN THE SUBSTRATE TO CONTACT THE RUBBERY POLYMER IN THE AREAS CORRESPONDING TO THE AREAS OF THE SUBSTRATE WHERE NO PRINTING APPEARS; (D) SEPARATING THE REPRODUCING SHEET FROM CONTACT WITH THE SUBSTRATE THEREBY RENDERING THE SOLVENT-TREATED AREA OPAQUE; AND (E) APPLYING A SHEET OF OPAQUE DARK-COLORED MATERIAL TO THE SIDE OF THE REPRODUCING LAMINATE WHICH BEARS THE THIN FILM OF RUBBERY POLYMER. 